Birth Small For Gestational Age Research Articles

Periconceptional folic acid supplementation and the risks of small and large for gestational age at birth: the mediation effect of maternal homocysteine level during pregnancy

BackgroundPericonceptional folic acid supplementation (FAS) is widely recommended. However, the role of periconceptional FAS on neonatal birth weight remains unclear. ObjectiveThis study aimed to explore the independent effects of periconceptional FAS on the risks of small for gestational age (SGA) and large for gestational age (LGA), and to test the potential mediation role of maternal homocysteine (Hcy) during pregnancy on the above significant associations. MethodsA large-scale prospective birth cohort was conducted in the Tongzhou Maternal and Child Health Hospital, Beijing, China from June 2018 to August 2019. Periconceptional FAS was evaluated by a self-administered questionnaire on the day of recruitment in early pregnancy (<14th week of gestation). FAS was defined as participants who had taken folic acid (FA) supplements, FA-containing multivitamins, or other FA-containing nutritional supplements. Neonatal birth weight was measured at delivery. Maternal serum Hcy concentrations were measured in early and late pregnancy respectively. Logistic regression analyses were performed to assess the associations between FAS during preconception and/or early pregnancy and the occurrence of SGA or LGA. A mediation model was constructed to determine the role of maternal Hcy concentration on the above associations. ResultsFAS before pregnancy (risk ratios [RR]=0.819, 95% confidence interval [CI]: 0.672-1.000, P=0.05), during early pregnancy (RR=0.622, 95%CI: 0.451-0.858) and from pre-pregnancy to early pregnancy (RR=0.564, 95%CI: 0.371-0.857) were associated with a lower risk of LGA. However, no significant association was found between periconceptional FAS and SGA birth. Maternal Hcy concentration in late pregnancy mediated the independent effects of maternal FAS during preconception and early pregnancy on the risks of LGA birth. ConclusionsPericonceptional FAS was associated with a lower risk of LGA, which may be mediated by the reduced serum Hcy concentration in late pregnancy. The current recommendation of periconceptional FAS should be complied with to reduce the risks of LGA.

Sustained decline in birth weight and increased rate of preterm infants born small for gestational age in Japan.

Birth weights have continued to decline in Japan in recent years. However, secular trend changes such as the birth weight relative to the week of gestation remain to be explored. This study aimed to determine the trends over time in mean birth weight and small for gestational age (SGA) rate for each gestational week. We used a large dataset of 27,015,792 births obtained from birth certificates between 1997 and 2021. Births from 22 to 41 weeks of gestation were evaluated in six groups (22-24, 25-27, 28-31, 32-33, 34-36, and 37-41 weeks of gestational age). For each group, secular trend changes in the z-scores calculated from standard birth weight values were assessed. Time trends in the proportion of SGA and mean birth weight z-scores were evaluated using the Cochran-Armitage trend test and linear regression analysis. Binomial logistic regression was performed to ascertain the effects of gestational age, sex, primiparity, number of births, and maternal age on the likelihood of SGA. The mean birth weight of preterm infants continued to decrease, and the z-score for mean birth weight decreased linearly, falling to -0.7 at 25-27 weeks of gestation from 1997-2001 (first period) to 2017-2021 (final period). Maternal age continued to increase from the first period to the last period for all weeks of gestation. There was a linear increase in the SGA rate in preterm infants born at <34 weeks. Odds ratios for the likelihood of SGA were 1.3 times higher for maternal age ≥40 years than that for 25-29 years (95% CI: 1.29-1.33, p < 0.001). In Japan, there has been a continuous decline in birth weight and an increase in the rate of preterm SGA infants.

Neonatal sex and maternal factors associated with small-for-gestational-age neonates: A nationwide population-based study.

Small-for-gestational-age (SGA) newborns have a higher risk of morbidity and mortality. Recognizing the risk factors for SGA helps raise early awareness of the issue and provides valuable insights for both healthcare providers and pregnant women. We aimed to identify determinants of SGA using population-based databases in Taiwan. Data were retrieved from the National Health Insurance, Birth Reporting, and Maternal and Child Health databases for this nationwide case-control study. Live births between 20 and 44 weeks of gestation from 2005 to 2014 were enrolled and linked to their mothers to determine maternal conditions during pregnancy. For every SGA newborn, four controls matched by gestational age and birth year were randomly selected. Multivariable logistic regression was used to identify risk factors for SGA, with adjusted odds ratios (aORs) and 95% confidence intervals (CIs) accounting for potential confounders and interaction terms. A total of 158,405 live SGA births were identified, with 623,584 controls randomly selected. Independent risk factors for SGA included maternal age <20 years (aOR 1.68, 95% CI 1.62, 1.75); female sex in newborns (aOR 1.28, 95% CI 1.27, 1.30); socioeconomic deprivation (aOR 1.29, 95% CI 1.21, 1.38); hypertension (aOR 1.6, 95% CI 1.52, 1.67); kidney disorders (aOR 1.29, 95% CI 1.16, 1.44); thyroid disorders (aOR 1.13, 95% CI 1.09, 1.17); systemic lupus erythematosus (aOR 2.59, 95% CI 2.33, 2.89); antiphospholipid syndrome (aOR 2.08, 95% CI 1.64, 2.64); gestational hypertension (aOR 1.69, 95% CI 1.61, 1.76); pre-eclampsia (aOR 3.12, 95% CI 3.01, 3.25); and antepartum hemorrhage (aOR 1.05, 95% CI 1.03, 1.07) after adjustment for other covariates. SGA was associated with younger maternal age, female newborns, underlying comorbidities, and obstetric conditions. Gestational hypertension and pre-eclampsia were significant risk factors affecting infants of both sexes and all age groups and could mask the effects of maternal age and infant sex.

Pregnancy Outcomes in Patients With Hepatitis C Virus Infection.

To evaluate the risks of adverse maternal and neonatal outcomes associated with pregnancies complicated by hepatitis C virus (HCV) infection. This is a secondary analysis of a multicenter prospective cohort study of HCV infection in pregnancy. Participants were screened for HCV infection with serum antibody tests, and each participant with a positive HCV result (case group) was matched with up to two individuals with negative HCV results (control group) prospectively by gestational age (±2 weeks) at enrollment. Maternal outcomes included gestational diabetes, abruption, preeclampsia or gestational hypertension, cholestasis, and preterm delivery. Neonatal outcomes included hyperbilirubinemia, admission to neonatal intensive care (NICU); small-for-gestational-age (SGA) birth weight; and neonatal infection, defined as sepsis or pneumonia. Models were adjusted for maternal age, body mass index, injection drug use, and maternal medical comorbidities. The 249 individuals in the case group were prospectively matched to 486 individuals in the control group who met eligibility criteria. There were significant differences in demographic characteristics between the groups, including race, socioeconomic markers, education, insurance status, and drug and tobacco use. The frequencies of maternal outcomes of gestational diabetes, preeclampsia, and abruption were similar between the case and control groups. Preterm birth was similar between groups, but neonates born to individuals in the case group were more likely to be admitted to the NICU (45.1% vs 19.0%, adjusted odds ratio [aOR] 2.6, 95% CI, 1.8-3.8) and to have SGA birth weights below the 5th percentile (10.6% vs 3.1%, aOR 2.9, 95% CI, 1.4-6.0). There were no increased odds of hyperbilirubinemia or neonatal infection. Despite no increased odds of preterm birth or other adverse maternal outcomes in adjusted analyses, maternal HCV infection was associated with twofold increased odds of NICU admission and nearly threefold increased odds of SGA birth weight below the 5th percentile.

Maternal Characteristics and Prevalence of Infants Born Small for Gestational Age

Being born small for gestational age (SGA) is a risk factor for neonatal mortality and adverse outcomes in the short and long term. The maternal profile in China has substantially changed over the past decade, which may affect the risk of infants born SGA. To analyze the prevalence of infants born SGA from 2012 through 2020 and explore the association of maternal sociodemographic characteristics and other factors with that prevalence. This cross-sectional study examined data from the National Maternal Near Miss Surveillance System on women who delivered singleton live births at gestational ages of 28 to 42 weeks from January 1, 2012, through December 31, 2020, in China. Statistical analysis was performed from December 2022 to September 2023. Characteristics of delivery (year, region of country, and hospital level), mother (age, educational level, marital status, prenatal visits, parity, preexisting diseases, or prenatal complications), and newborn (birth weight, sex, and gestational age). Prevalence of infants born SGA stratified by severity and by region of the country, changes in prevalence based on log-linear Poisson regression with robust variance, and association of maternal characteristics with changes in prevalence of infants born SGA between 2012 and 2020 based on the Fairlie nonlinear mean decomposition. Among 12 643 962 births (6 572 548 [52.0%] male; median gestational age, 39 weeks [IQR, 38-40 weeks]), the overall weighted prevalence of infants born SGA was 6.4%, which decreased from 7.3% in 2012 to 5.3% in 2020, translating to a mean annual decrease rate of 3.9% (95% CI, 3.3%-4.5%). The prevalence of infants born SGA decreased from 2.0% to 1.2% for infants with severe SGA birth weight and from 5.3% to 4.1% for those with mild to moderate SGA birth weight. The mean annual rate of decrease was faster for infants with severe SGA birth weight than for those with mild to moderate SGA birth weight (5.9% [95% CI, 4.6%-7.1%] vs 3.2% [95% CI, 2.6%-3.8%]) and was faster for the less developed western (5.3% [95% CI, 4.4%-6.1%]) and central (3.9% [95% CI, 2.9%-4.8%]) regions compared with the eastern region (2.3% [95% CI, 1.1%-3.4%]). Two-thirds of the observed decrease in the prevalence of infants born SGA could be accounted for by changes in maternal characteristics, such as educational level (relative association, 19.7%), age (relative association, 18.8%), prenatal visits (relative association, 20.4%), and parity (relative association, 19.4%). Conversely, maternal preexisting diseases or prenatal complications counteracted the decrease in the prevalence of infants born SGA (-6.7%). In this cross-sectional study of births in China from 2012 to 2020, maternal characteristics changed and the prevalence of infants born SGA decreased. Future interventions to reduce the risk of infants born SGA should focus on primary prevention.

Small for Gestational Age Calves: Part I-Concept and Definition, Contributing Prenatal Factors and Neonatal Body Morphometrics in Holstein Friesian Calves.

Low birth weight (BW) calves exhibit higher mortality rates, reduced body weights at parturition, lower first-lactation milk yields, and longer parturition to first insemination intervals. In human medicine, small for gestational age (SGA) births are associated with increased perinatal morbidity and long-term metabolic risks. This study aimed to define SGA in Holstein Friesian (HF) calves, evaluate their body measurements and proportions, and identify its prenatal risk factors. Four linear regression models were built with weight as a function for gestation length for bull and heifer calves born from nulli- or multiparous dams. Calves with a BW below the 10th percentile were classified as SGA. Differences in body measurements were analyzed using ANOVA, and logistic regression models identified prenatal risk factors to be born SGA. Gestation length, calf sex, and dam parity were crucial variables in defining SGA. SGA calves had significantly smaller body measurements (p < 0.001) and larger body proportions (p < 0.001) compared to average and large calves. For nulliparous dams, a higher 2nd trimester temperature-humidity index (p = 0.032) and older age at parturition (>26 months, p = 0.026) significantly increased the birth of SGA calves. For multiparous dams, both low (<5800 kg, p = 0.049) and high (6700-8600 kg, p = 0.027) milk yields during gestation lead to more SGA births, although very high-yielding dams (>8600 kg) did not birth more SGA calves. This study establishes SGA in HF calves, suggests SGA calves are asymmetrical with evidence of "brain sparing", and highlights the impact of prenatal factors on calf size at birth. Further research is needed to determine the long-term effects of being born SGA on growth, reproductive performance, and productivity.

Ethno-racial inequalities on adverse birth and neonatal outcomes: a nationwide, retrospective cohort study of 21 million Brazilian newborns

Ethno-racial inequalities are critical determinants of health outcomes. We quantified ethnic-racial inequalities on adverse birth outcomes and early neonatal mortality in Brazil. We conducted a cohort study in Brazil using administrative linked data between 2012 and 2019. Estimated the attributable fractions for the entire population (PAF) and specific groups (AF), as the proportion of each adverse outcome that would have been avoided if all women had the same baseline conditions as White women, both unadjusted and adjusted for socioeconomics and maternal risk factors. AF was also calculated by comparing women from each maternal race/skin colour group in different groups of mothers' schooling, with White women with 8 or more years of education as the reference group and by year. 21,261,936 newborns were studied. If all women experienced the same rate as White women, 1.7% of preterm births, 7.2% of low birth weight (LBW), 10.8% of small for gestational age (SGA) and 11.8% of early neonatal deaths would have been prevented. Percentages preventable were higher among Indigenous (22.2% of preterm births, 17.9% of LBW, 20.5% of SGA and 19.6% of early neonatal deaths) and Black women (6% of preterm births, 21.4% of LBW, 22.8% of SGA births and 20.1% of early neonatal deaths). AF was higher in groups with fewer years of education among Indigenous, Black and Parda for all outcomes. AF increased over time, especially among Indigenous populations. A considerable portion of adverse birth outcomes and neonatal deaths could be avoided if ethnic-racial inequalities were non-existent in Brazil. Acting on the causes of these inequalities must be central in maternal and child health policies. Bill & Melinda Gates Foundation and Wellcome Trust.

Organophosphate Ester Flame Retardants and Plasticizers in Relation to Fetal Growth in the LIFECODES Fetal Growth Study.

Organophosphate esters (OPEs), used ubiquitously as flame retardants and plasticizers in consumer products, are suspected of having developmental toxicity. Our study aimed to estimate associations between prenatal exposure to OPEs and fetal growth, including both ultrasound (head circumference, abdominal circumference, femur length, and estimated fetal weight) and delivery [birth weight z-score, small-for-gestational age (SGA), and large-for-gestational age (LGA)] measures of growth. In the LIFECODES Fetal Growth Study (2008-2018), an enriched case-cohort of 900 babies born at the small and large ends of the growth spectrum, we quantified OPE biomarkers in three urine samples per pregnant participant and abstracted ultrasound and delivery measures of fetal growth from medical records. We estimated associations between pregnancy-averaged log-transformed OPE biomarkers and repeated ultrasound measures of fetal growth using linear mixed-effects models, and delivery measures of fetal growth using linear (birth weight) and logistic (SGA and LGA) regression models. Most OPE biomarkers were positively associated with at least one ultrasound measure of fetal growth, but associations with delivery measures were largely null. For example, an interquartile range (IQR; ) increase in bis(2-chloroethyl) phosphate concentration was associated with larger z-scores in head circumference [mean difference (difference): 0.09; 95% confidence interval (CI): 0.01, 0.17], abdominal circumference (difference: 0.10; 95% CI: 0.02, 0.18), femur length (difference: 0.11; 95% CI: 0.03, 0.19), and estimated fetal weight (difference: 0.13; 95% CI: 0.04, 0.22) but not birth weight (difference: 0.04; 95% CI: , 0.17). At delivery, an IQR () increase in diphenyl phosphate (DPHP) concentration was associated with an SGA birth (odds ratio: 1.46; 95% CI: 1.10, 1.94). In a large prospective cohort, gestational OPE exposures were associated with larger fetal size during pregnancy, but associations at delivery were null. DPHP concentrations were associated with heightened risk of an SGA birth. These findings suggest that OPE exposure may affect fetal development. https://doi.org/10.1289/EHP14647.

Risk factors for bronchopulmonary dysplasia in twin preterm infants: a multicenter study

To investigate the risk factors for bronchopulmonary dysplasia (BPD) in twin preterm infants with a gestational age of <34 weeks, and to provide a basis for early identification of BPD in twin preterm infants in clinical practice. A retrospective analysis was performed for the twin preterm infants with a gestational age of <34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020. According to their conditions, they were divided into group A (both twins had BPD), group B (only one twin had BPD), and group C (neither twin had BPD). The risk factors for BPD in twin preterm infants were analyzed. Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins. A total of 904 pairs of twins with a gestational age of <34 weeks were included in this study. The multivariate logistic regression analysis showed that compared with group C, birth weight discordance of >25% between the twins was an independent risk factor for BPD in one of the twins (OR=3.370, 95%CI: 1.500-7.568, P<0.05), and high gestational age at birth was a protective factor against BPD (P<0.05). The conditional logistic regression analysis of group B showed that small-for-gestational-age (SGA) birth was an independent risk factor for BPD in individual twins (OR=5.017, 95%CI: 1.040-24.190, P<0.05). The development of BPD in twin preterm infants is associated with gestational age, birth weight discordance between the twins, and SGA birth.

Effects of the COVID-19 pandemic on the rates of adverse birth outcomes and fetal mortality in Japan: an analysis of national data from 2010 to 2022

BackgroundAlthough the coronavirus disease 2019 (COVID-19) pandemic affected trends of multiple health outcomes in Japan, there is a paucity of studies investigating the effect of the pandemic on adverse birth outcomes and fetal mortality. This study aimed to investigate the effect of the onset of the pandemic on the trends in adverse birth outcomes and fetal mortality using national data in Japan.MethodsWe used the 2010–2022 birth and fetal mortality data from the Vital Statistics in Japan. We defined the starting time of the effect of the pandemic as April 2020, and the period from January 2010 to March 2020 and that from April 2020 to December 2022 were defined as the pre- and post- pandemic period, respectively. The rates of preterm birth, term low birth weight (TLBW), small-for-gestational-age (SGA), large-for-gestational-age (LGA), spontaneous fetal mortality, and artificial fetal mortality were used as outcomes. An interrupted time series analysis was conducted using monthly time series data of the outcomes to evaluate the effects of the pandemic. In addition, a modified Poisson regression model was used to evaluate the effects of the pandemic on these outcomes using individual-level data, and the adjusted risk ratio of the effect was calculated.ResultsThe adverse birth and fetal mortality outcomes showed a decreasing trend over the years, except for preterm birth and LGA birth rates, and SGA birth rates tended to reach their lowest values after the onset of the pandemic. The interrupted time series analysis revealed that the pandemic decreased preterm birth, TLBW, and SGA birth rates. In addition, the regression analysis revealed that the pandemic decreased the TLBW, SGA, and artificial fetal mortality rates.ConclusionsAnalyses performed using national data suggested that the pandemic decreased the TLBW and SGA rates in Japan.

Hemoglobin A1c Trajectories During Pregnancy and Adverse Outcomes in Women With Type 2 Diabetes: A Danish National Population-Based Cohort Study.

To identify and characterize groups of pregnant women with type 2 diabetes with distinct hemoglobin A1c (HbA1c) trajectories across gestation and to examine the association with adverse obstetric and perinatal outcomes. This was a retrospective Danish national cohort study including all singleton pregnancies in women with type 2 diabetes, giving birth to a liveborn infant, between 2004 and 2019. HbA1c trajectories were identified using latent class linear mixed-model analysis. Associations with adverse outcomes were examined with logistic regression models. A total of 1,129 pregnancies were included. Three HbA1c trajectory groups were identified and named according to the glycemic control in early pregnancy (good, 59%; moderate, 32%; and poor, 9%). According to the model, all groups attained an estimated HbA1c <6.5% (48 mmol/mol) during pregnancy, with no differences between groups in the 3rd trimester. Women with poor glycemic control in early pregnancy had lower odds of having an infant with large-for-gestational-age (LGA) birth weight (adjusted odds ratio [aOR] 0.57, 95% CI 0.40-0.83), and higher odds of having an infant with small-for-gestational age (SGA) birth weight (aOR 2.49, 95% CI 2.00-3.10) and congenital malformation (CM) (aOR 4.60 95% CI 3.39-6.26) compared with women with good glycemic control. There was no evidence of a difference in odds of preeclampsia, preterm birth, and caesarean section between groups. Women with poor glycemic control in early pregnancy have lower odds of having an infant with LGA birth weight, but higher odds of having an infant with SGA birth weight and CM.

Effects of ambient air pollution on the risk of small- and large-for-gestational-age births: an analysis using national birth data in Japan.

Small-for-gestational-age (SGA) and large-for-gestational-age (LGA) births are major adverse birth outcomes related to newborn health. In contrast, the association between ambient air pollution levels and SGA or LGA births has not been investigated in Japan; hence, the purpose of our study is to investigate this association. We used birth data from Vital Statistics in Japan from 2017 to 2021 and municipality-level data on air pollutants, including nitrogen dioxide (NO2), sulfur dioxide (SO2), photochemical oxidants, and particulate matter 2.5 (PM2.5). Ambient air pollution levels throughout the first, second, and third trimesters, as well as the whole pregnancy, were calculated for each birth. The association between SGA/LGA and ambient levels of the air pollutants was investigated using crude and adjusted log-binomial regression models. In addition, a regression model with spline functions was also used to detect the non-linear association. We analyzed data from 2,434,217 births. Adjusted regression analyses revealed statistically significant and positive associations between SGA birth and SO2 level, regardless of the exposure period. Specifically, the risk ratio for average SO2 values throughout the whole pregnancy was 1.014 (95% confidence interval [CI] 1.009, 1.019) per 1ppb increase. In addition, regression analysis with spline functions indicated that an increase in risk ratio for SGA birth depending on SO2 level was linear. Furthermore, statistically significant and negative associations were observed between LGA birth and SO2 except for the third trimester. It was suggested that ambient level of SO2 during the pregnancy term is a risk factor for SGA birth in Japan.

Birth and postnatal outcomes among infants of immigrant parents of different admission categories and parents born in Canada: a population-based retrospective study.

Most studies of disparities in birth and postnatal outcomes by parental birthplace combine all immigrants into a single group. We sought to evaluate heterogeneity among immigrants in Canada by comparing birth and postnatal outcomes across different immigration categories. We conducted a population-based retrospective study using Statistics Canada data on live births and stillbirths (1993-2017) and infant deaths (1993-2018), linked to parental immigration data (1960-2017). We classified birthing parents as born in Canada, economic-class immigrants, family-class immigrants, or refugees, and evaluated differences in preterm births, small-for-gestational-age (SGA) and large-for-gestational-age (LGA) births, stillbirths, and infant deaths among singleton births by group. Among 7 980 650 births, 1 715 050 (21.5%) were to immigrants, including 632 760 (36.9%) in the economic class, 853 540 (49.8%) in the family class, and 228 740 (13.4%) refugees. Compared with infants of Canadian-born birthing parents, infants of each of the 3 immigrant groups had higher risk of preterm birth, SGA birth, and stillbirth, but lower risk of LGA birth and neonatal death. Compared with infants of economic-class immigrants, infants of refugees had higher risk of early preterm birth (0.9% v. 0.8%, adjusted risk ratio [RR] 1.08, 95% confidence interval [CI] 1.01-1.15) and LGA birth (9.2% v. 7.5%, adjusted RR 1.12, 95% CI 1.10-1.15), but lower risk of SGA birth (10.2% v. 11.0%, adjusted RR 0.92, 95% CI 0.90-0.94), while infants of family-class immigrants had higher risk of SGA birth (12.2% v. 11.0%, adjusted RR 1.01, 95% CI 1.00-1.02). Risk of stillbirth, neonatal death, and overall infant death did not differ significantly among immigrant groups. Heterogeneity exists in outcomes of infants born to immigrants to Canada across immigration categories. These results highlight the importance of disaggregating immigrant populations in studies of health disparities.

Risk of Adverse Perinatal Outcomes Among African-born Black Women in California, 2011-2020.

African-born women have a lower risk of preterm birth and small for gestational age (SGA) birth compared with United States-born Black women, however variation by country of origin is overlooked. Additionally, the extent that nativity disparities in adverse perinatal outcomes to Black women are explained by individual-level factors remains unclear. We conducted a population-based study of nonanomalous singleton live births to United States- and African-born Black women in California from 2011 to 2020 (n = 194,320). We used age-adjusted Poisson regression models to estimate the risk of preterm birth and SGA and reported risk ratios (RR) and 95% confidence intervals (CI). Decomposition using Monte Carlo integration of the g-formula computed the percentage of disparities in adverse outcomes between United States- and African-born women explained by individual-level factors. Eritrean women (RR = 0.4; 95% CI = 0.3, 0.5) had the largest differences in risk of preterm birth and Cameroonian women (RR = 0.5; 95% CI = 0.3, 0.6) in SGA birth, compared with United States-born Black women. Ghanaian women had smaller differences in risk of preterm birth (RR = 0.8; 95% CI = 0.7, 1.0) and SGA (RR = 0.9; 95% CI = 0.8, 1.1) compared with United States-born women. Overall, we estimate that absolute differences in socio-demographic and clinical factors contributed to 32% of nativity-based disparities in the risk of preterm birth and 26% of disparities in SGA. We observed heterogeneity in risk of adverse perinatal outcomes for African- compared with United States-born Black women, suggesting that nativity disparities in adverse perinatal outcomes were not fully explained by differences in individual-level factors.

Neonatal Outcomes among Fetuses with an Abdominal Circumference

Fetal growth restriction (FGR) is defined as an estimated fetal weight (EFW) or abdominal circumference (AC) <10th percentile (%ile) for gestational age (GA). An EFW <3rd %ile for GA is considered severe FGR (sFGR). It remains unknown if fetuses with isolated AC <3rd %ile should be considered sFGR. Our primary objective was to assess composite neonatal outcomes in fetuses with an AC <3rd %ile and overall EFW 3rd to 9th %ile compared with those with an EFW <3rd %ile. This retrospective cohort study was undertaken at a tertiary academic center from January 2016 to December 2021. Inclusion criteria were singleton fetuses with an EFW <3rd %ile (Group 1) or AC <3rd %ile with EFW 3rd to 9th %ile (Group 2) at 28 weeks' gestation or greater. Exclusion criteria were multiple gestations, presence of a major fetal anomaly, resolution of FGR, genetic syndrome, or infection. Composite neonatal outcome was defined by any of the following: neonatal intensive care unit admission >48 hours, necrotizing enterocolitis, sepsis, respiratory distress syndrome, mechanical ventilation, retinopathy of prematurity, seizures, intraventricular hemorrhage, stillbirth, or death before discharge. Small for gestational age (SGA) was defined as birth weight <10th %ile for GA. A total of 743 patients fulfilled our study criteria, with 489 in Group 1 and 254 in Group 2. The composite neonatal outcome occurred in 281 (57.5%) neonates in Group 1 and 53 (20.9%) in Group 2 (p < 0.01). The rates of SGA at birth were 94.9 and 75.6% for Group 1 and Group 2, respectively (OR 5.99, 95% confidence interval 3.65-9.82). Although AC <3rd %ile with EFW 3rd to 9th %ile is associated with a lower frequency of SGA and neonatal morbidity than EFW <3 %ile, fetuses with AC <3 %ile still exhibited moderate rates of these adverse perinatal outcomes. Consideration should be given to inclusion of an AC <3rd %ile with EFW 3rd to 9th %ile as a criterion for sFGR. However, prospective studies comparing delivery at 37 versus 38 to 39 weeks' gestation are needed to ensure improved outcomes before widespread adaptation in clinical practice. · The composite neonatal outcome occurred in 57.5% of fetuses with an overall EFW <3rd %ile and 20.9% of fetuses with an AC <3rd %ile but EFW 3rd to 9th %ile.. · Both groups demonstrated a high positive predictive value for SGA birth weight.. · Consideration should be given to inclusion of an AC <3rd %ile as a criterion for sFGR..

Evaluation of neonatal outcomes according to the specific absorption rate values of phones used during pregnancy.

The aim was to compare neonatal outcomes according to cell phone specific absorption rate (SAR) levels and daily time spent on cell phones by pregnant women. Women who gave birth at Konya City Hospital between September 2020 and February 2021 were included in this retrospective study. Gestational ages, birth weight, birth length, head circumference, sex, 5-minute APGAR scores, neonate postpartum resuscitation requirement, delivery type, the model of phone used by the pregnant women, and the average time spent on the phone during a day were recorded. To determine the relation between the SAR values of the phones used and delivering a small for gestational age (SGA) baby, receiver operating characteristic curve analysis was performed. In total 1495 pregnant women were included. The rate of delivering a SGA fetus was significantly higher in women who used phones with higher SAR values (p=0.001). The cut-off value for the SAR level was 1.23 W/kg with 69.3% sensitivity and 73.0% specificity (area under the curve: 0.685; 95% confidence interval: 0.643-0.726). No correlation was found between time spent on the phone and SGA birth rate. Although both phone SAR values and time spent on the phone were higher in the symmetrical SGA group compared to the asymmetrical SGA group, the difference was not significant (p>0.05). Although the women who had preterm delivery had higher phone SAR values and had spent more time on the phone compared to those who had term deliveries, the difference was again not significant (p>0.05). As the SAR values of cell phones used during pregnancy increased, there was a trend towards delivering a SGA baby.

Association between infant birth weight and gestational weight gain in Japanese women with diabetes mellitus.

In 2021, the guidelines on gestational weight gain (GWG) were revised and increased by 2-3 kg in Japan. This study aimed to investigate whether the revised guidelines would increase the incidence of babies with excessive birth weight in mothers with diabetes. This retrospective study included 369 deliveries of women with diabetes whose pre-pregnancy body mass index was below 30 kg/m2 between 1982 and 2021. The primary outcome measure was large for gestational age (LGA). We compared the incidence of LGA between women who gained weight within the previous guidelines and women who gained weight within the revised guidelines. We also compared the incidence of macrosomia, preeclampsia, small for gestational age (SGA), and low birth weight. The incidence of LGA was not significantly different between women who gained weight within the revised guidelines and those within the previous guidelines (34.6% [95% confidence interval 25.6-44.6%] for the revised guidelines vs 28.9% [21.6-37.1%] for the previous guidelines; P = 0.246). Neither was the incidence of macrosomia or preeclampsia significantly different (8.7% [4.0-15.8%] vs 5.6% [2.5-10.8%] and 5.8% [2.1-12.1%] vs 6.3% [2.9-11.7%]; P = 0.264 and 0.824, respectively), while women who gained weight within the revised guidelines had a lower incidence of SGA (1.9% [0.2-6.8%] vs 10.6% [6.0-16.8%]; P = 0.001) and low birth weight (1.0% [0.02-5.2%] vs 7.0% [3.4-12.6%]; P = 0.023). The revised GWG guidelines could be beneficial in women with diabetes in terms of delivering babies with appropriate birth weight.

The Population-Attributable Fractions of Small-for-Gestational-Age Births: Results from the Japan Birth Cohort Consortium.

A fetal growth restriction is related to adverse child outcomes. We investigated risk ratios and population-attributable fractions (PAF) of small-for-gestational-age (SGA) infants in the Japanese population. Among 28,838 infants from five ongoing prospective birth cohort studies under the Japan Birth Cohort Consortium, two-stage individual-participant data meta-analyses were conducted to calculate risk ratios and PAFs for SGA in advanced maternal age, pre-pregnancy underweight, and smoking and alcohol consumption during pregnancy. Risk ratio was calculated using modified Poisson analyses with robust variance and PAF was calculated in each cohort, following common analyses protocols. Then, results from each cohort study were combined by meta-analyses using random-effects models to obtain the overall estimate for the Japanese population. In this meta-analysis, an increased risk (risk ratio, [95% confidence interval of SGA]) was significantly associated with pre-pregnancy underweight (1.72 [1.42-2.09]), gestational weight gain (1.95 [1.61-2.38]), and continued smoking during pregnancy (1.59 [1.01-2.50]). PAF of underweight, inadequate gestational weight gain, and continued smoking during pregnancy was 10.0% [4.6-15.1%], 31.4% [22.1-39.6%], and 3.2% [-4.8-10.5%], respectively. In conclusion, maternal weight status was a major contributor to SGA births in Japan. Improving maternal weight status should be prioritized to prevent fetal growth restriction.

Associations of Night Shift Status During Pregnancy With Small for Gestational Age and Preterm Births.

Shift work, including night shift work, during pregnancy has been associated with adverse birth outcomes such as small for gestational age (SGA) infants and preterm births. This study, conducted in South Korea using the Korean CHildren's ENvironmental health Study (Ko-CHENS) cohort, aimed to investigate the association between shift work and night shift status during pregnancy and adverse birth outcomes. The Korean Ko-CHENS is a nationwide prospective birth cohort study of children's environmental diseases, conducted by the Ministry of Environment and the National Institute of Environmental Research. This study included pregnant women recruited from 2015 to 2020 for Ko-CHENS Core Cohorts, and 4,944 out of a total of 5,213 pregnant women were selected as final subjects. A logistic regression model was used to identify the risk factors affecting SGA births, preterm births, and low-birth-weight infants, and the odds ratio (OR) was adjusted. This was confirmed by calculating ORs. Maternal age, infant sex, maternal educational status, body mass index, smoking status, alcohol consumption status, parity, gestational diabetes mellitus, preeclampsia, and abortion history were used as adjusted variables. No statistically significant differences were observed in the birth outcomes or maternal working patterns. There were no significant differences in the adjusted odds ratios (aORs) of SGA and preterm births between the non-worker, day worker, and shift worker. However, there was a significant difference in the aORs of SGA between non-workers and night shift workers. (aORs [95% confidence interval], 2.643 [1.193-5.859]). Working during pregnancy did not increase the risk of SGA or preterm birth, and night shift work did not increase the risk of preterm birth. However, night-shift work increases the risk of SGA.

Periconceptional Dietary Patterns and Adverse Pregnancy and Birth Outcomes

BackgroundThe periconceptional period is a critical window for the origins of adverse pregnancy and birth outcomes, yet little is known about the dietary patterns that promote perinatal health. ObjectiveWe used machine learning methods to determine the effect of periconceptional dietary patterns on risk of preeclampsia, gestational diabetes, preterm birth, small-for-gestational-age (SGA) birth, and a composite of these outcomes. MethodsWe used data from 8259 participants in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (8 US medical centers, 2010‒2013). Usual daily periconceptional intake of 82 food groups was estimated from a food frequency questionnaire. We used k-means clustering with a Euclidean distance metric to identify dietary patterns. We estimated the effect of dietary patterns on each perinatal outcome using targeted maximum likelihood estimation and an ensemble of machine learning algorithms, adjusting for confounders including health behaviors and psychological, neighborhood, and sociodemographic factors. ResultsThe 4 dietary patterns that emerged from our data were identified as “Sandwiches and snacks” (34% of the sample); “High fat, sugar, and sodium” (29%); “Beverages, refined grains, and mixed dishes” (21%); and “High fruits, vegetables, whole grains, and plant proteins” (16%). One-quarter of pregnancies had preeclampsia (8% incidence), gestational diabetes (5%), preterm birth (8%), or SGA birth (8%). Compared with the “High fat, sugar, and sodium” pattern, there were 3.3 to 4.3 fewer cases of the composite adverse outcome per 100 pregnancies among participants following the “Beverages, refined grains and mixed dishes” pattern (risk difference −0.043; 95% confidence interval −0.078, −0.009), “High fruits, vegetables, whole grains and plant proteins” pattern (−0.041; 95% confidence interval −0.078, −0.004), and “Sandwiches and snacks” pattern (−0.033; 95% confidence interval −0.065, −0.002). ConclusionsOur results highlight that there are a variety of periconceptional dietary patterns that are associated with perinatal health and reinforce the negative health implications of diets high in fat, sugars, and sodium.